Note 8 - Income Taxes (Details Textual) - USD ($) $ in Millions	9 Months Ended
Jun. 30, 2023	Jun. 30, 2022
Effective Income Tax Rate Reconciliation, Percent	26.20%	23.00%
State and Local Jurisdiction [Member] \| California Franchise Tax Board [Member]
Unrecognized Tax Benefits that Would Impact Effective Tax Rate		$ (0.2)

The total amount of unrecognized tax benefits that, if recognized, would affect the effective tax rate.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 15A
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482685/740-10-50-15A

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant